Mr. Salton, too, showed much interest in the job, and was constantly coming in and out, nothing escaping his observation.

Since her marriage to Adam and their coming to stay at Doom Tower, Mimi had been fettered by fear of the horrible monster at Diana’s Grove.  But now she dreaded it no longer.  She accepted the fact of its assuming at will the form of Lady Arabella.  She had still to tax and upbraid her for her part in the unhappiness which had been wrought on Lilla, and for her share in causing her death.

One evening, when Mimi entered her own room, she went to the window and threw an eager look round the whole circle of sight.  A single glance satisfied her that the White Worm in propria persona was not visible.  So she sat down in the window-seat and enjoyed the pleasure of a full view, from which she had been so long cut off.  The maid who waited on her had told her that Mr. Salton had not yet returned home, so she felt free to enjoy the luxury of peace and quiet.

As she looked out of the window, she saw something thin and white move along the avenue.  She thought she recognised the figure of Lady Arabella, and instinctively drew back behind the curtain.  When she had ascertained, by peeping out several times, that the lady had not seen her, she watched more carefully, all her instinctive hatred flooding back at the sight of her.  Lady Arabella was moving swiftly and stealthily, looking back and around her at intervals, as if she feared to be followed.  This gave Mimi an idea that she was up to no good, so she determined to seize the occasion for watching her in more detail.

Hastily putting on a dark cloak and hat, she ran downstairs and out into the avenue.  Lady Arabella had moved, but the sheen of her white dress was still to be seen among the young oaks around the gateway.  Keeping in shadow, Mimi followed, taking care not to come so close as to awake the other’s suspicion, and watched her quarry pass along the road in the direction of Castra Regis.

She followed on steadily through the gloom of the trees, depending on the glint of the white dress to keep her right.  The wood began to thicken, and presently, when the road widened and the trees grew farther back, she lost sight of any indication of her whereabouts.  Under the present conditions it was impossible for her to do any more, so, after waiting for a while, still hidden in the shadow to see if she could catch another glimpse of the white frock, she determined to go on slowly towards Castra Regis, and trust to the chapter of accidents to pick up the trail again.  She went on slowly, taking advantage of every obstacle and shadow to keep herself concealed.

At last she entered on the grounds of the Castle, at a spot from which the windows of the turret were dimly visible, without having seen again any sign of Lady Arabella.